Detection of Cerebral Microbleeding By Susceptibility Weighted Imaging Sequence and Research on Relation Between CMBs and Risk Factors

目的 探讨磁敏感加权成像(susceptibility weighted imaging sequence,SWI)检测脑微出血(cerebral microb-leeds,CMBs)的优势,并分析CMBs的相关临床危险因素及其临床意义.资料与方法 经磁共振常规序列及SWI序列检测CMBs,搜集189例患者,其中CMBs阳性者79例,且经蒙特利尔认知评估(MoCA)量表及简易智能状态检查量表(MMSE)评价CMBs阳性患者的认知功能情况.结果 SWI对CMBs的病灶检出数较常规序列明显增多;CMBs主要分布在颞叶及基底节区,高血压、糖尿病、白质严重程度、急性梗死及腔隙性梗死与CMBs的存在与否有显著性差异(P＜0.01),且CMBs阳性患者的MoCA量表总分(r=-0.86,P＜0.00)及MMSE总分(r=-0.79,P＜0.00)与CMBs总数呈明显负相关.结论 SWI较常规序列能更好地显示CMBs,具有重要的临床价值;高血压、糖尿病、白质改变、急性梗死及腔隙性梗死与CMBs的存在有密切相关性,大量CMBs与患者认知功能受损密切相关.     

SWI对急性期脑梗死合并脑微出血的诊断价值及临床相关因素研究

目的:探讨SWI对急性期脑梗死合并脑微出血(cerebralmicrobleeds,CMBs)的诊断价值及急性期脑梗死合并CMBs的危险因素。方法:选取急性期脑梗死患者62例,采用GE Signa HDX 3.0T超导型MR仪,行常规MRI及DWI、SWI序列。并结合临床相关资料,研究分析:①SWI对急性期脑梗死患者CMBs的检出率和CMBs在SWI的分布特点;②结合患者性别,年龄及有无高血压、糖尿病、高脂血症、心脏病等6项临床相关因素,分析急性期脑梗死合并CMBs的危险因素。结果:MRI常规序列、DWI及SWI对62例急性期脑梗死合并CMBs的阳性检出率分别为:0.00%,8.06%,40.32%,差异具有统计学意义,SWI的阳性检出率高于常规MRI检查和DWI序列。CMBs在SWI分布特点:25例急性期脑梗死合并CMBs的CMBs灶均为多发病灶,在脑内各个区域分布不等,以基底节-丘脑区最多,其次为皮质-皮质下区,脑干和小脑最少。患者的年龄、高血压与急性期脑梗死合并CMBs有相关性(P<0.05),年龄(OR=1.704,95%CI 0.029～2.840,P<0.001)和高血压OR=1.039,95%CI 1.003～1.588,P=0.019)是急性期脑梗死合并CMBs的危险因素。糖尿病、高脂血症、心脏病等与急性期脑梗死合并CMBs无相关性(P>0.05)。结论:SWI对急性期脑梗死合并CMBs的检出比常规MRI和DWI有优势,是检出CMBs的较好检查技术。年龄、高血压是急性期脑梗死合并CMBs的独立危险因素。     

利用SWI探讨急性脑梗死合并脑微出血静脉溶栓风险

目的：探讨急性脑梗死合并脑微出血(CMBs)的相关危险因素及静脉溶栓治疗后出血转化风险。方法收集164急性脑梗死患者,入院时均行常规 MRI 及 SWI 扫描,根据 SWI 上有无 CMBs 分为 CMBs 阳性组和 CMBs 阴性组,记录所有患者的一般临床资料,探讨 CMBs 的相关危险因素。静脉溶栓治疗后的76例患者,其中 CMBs 阳性组35例,CMBs 阴性组41例,分别计数2组患者 CMBs 数目增多或出现出血转化的例数。结果年龄、高血压病、腔隙性梗死、脑白质疏松与 CMBs 相关性显著(P <0.05)。静脉溶栓后2组患者间出血转化率差异无统计学意义(P >0.05)。结论性别、年龄、高血压病、腔隙性脑梗死、脑白质疏松是CMBs 的危险因素。急性脑梗死合并 CMBs 患者静脉溶栓治疗不会增加出血转化危险。     

MRI在脑微出血与腔隙性脑梗死相关性研究中的应用

目的:利用MRI研究脑微出血(CMBs)与腔隙性脑梗死的相关性。方法:收集颅脑MRI受检者284例,行常规MRI序列及磁敏感加权成像(SWI)序列扫描。记录CMBs及腔隙性脑梗死位置、数目,分析CMBs、腔隙性脑梗死分布位置以及病变程度,分别统计皮层-皮层下区(CSC区)、基底节-丘脑区(DGM区)、幕下区(IT区)的CMBs、腔隙性脑梗死数目并进行相应分级;再根据脑内所有CMBs及腔隙性脑梗死数目总和对每例患者进行分级,分析两者在发病部位、病变等级之间相关性,统计各年龄组CMBs、腔隙性脑梗死发生率。利用SPSS 13.0软件对数据进行统计分析。结果:284例受检者中腔隙性脑梗死215例,CMBs 97例,腔隙性脑梗死患者CMBs发生率约40%。CMBs、腔隙性脑梗死数目分别为1～93、1～41个不等;CMBs、腔隙性脑梗死具有共同的好发部位,CSC区rs=0.450,P=0.004;DGM区,rs=0.406,P=0.000;IT区,rs=0.441,P=0.000。CSC区、DGM区、IT区的CMBs病变程度随腔隙性脑梗死病变程度的升高而升高(P=0.000);脑内所有CMBs与腔隙性脑梗死病变程度呈显著相关性(P=0.000);腔隙性脑梗死、CMBs的发生率随年龄的增大而升高。结论:颅脑MRI常规扫描序列结合SWI序列检测腔隙性脑梗死和CMBs,可以更加科学指导脑血管患者的诊断治疗、跟踪观察及预后判断。     

SWI在高血压患者伴发脑内微出血的诊断应用

目的 了解高血压患者伴发脑内微出血(CMBs)在磁敏感加权成像(SWI)上的表现,并探讨其与高血压水平、白质疏松程度、伴发梗死和叶性出血的关系及其病理基础.资料与方法 对59例高血压患者行SWI,观察CMBs在SWI上的表现,对其数目和分布进行统计并进一步与临床和其他影像资料进行相关分析.结果 59例共检出35例(59%)CMBs,CMBs呈典型顺磁性物质相位图改变.CMBs主要分布于皮层和皮层下(1,0～5)、基底节区(3,0～10);脑内有CMBs组平时收缩压水平为(154.4±15.0)mmHg(1 mmHg=0.133 kPa)和平时舒张压水平为(92.6±12.6)mmHg均高于无CMBs组;不同级别白质疏松者相对应的CMBs数目有显著性差异;有伴发梗死或出血组的CMBs数目高于无伴发组.结论 SWI有助于显示CMBs;高血压患者CMBs主要分布于基底节区以及皮层和皮层下区;CMBs的出现和多少间接反映了脑内细微穿支动脉的受损程度.     

阿尔茨海默病患者联络纤维的DTI诊断价值

目的采用磁共振扩散张量成像(diffusion tensor imaging,DTI)观察阿尔茨海默病(Alzheimer’s disease,AD)患者联络纤维的改变情况。资料与方法对10例轻中度AD患者和18名健康老年人(对照组)行常规MRI[(T1WI、T2WI、T2液体衰减反转恢复序列(FLAIR)]及DTI检查,DTI测量双侧扣带束、上纵束Ⅱ、钩束及额枕下束8个感兴趣区(ROI)的部分各向异性分数(FA)值。采用简易精神状态量表(MMSE)和蒙特利尔认知评估量表(MoCA)对AD患者的认知功能进行测定。结果与对照组相比,AD组MMSE评分和MoCA评分较对照组明显下降(P<0.05),AD组常规MRI上ROI白质信号无明显变化,ROI部位的FA值均显著下降(P<0.05),且上纵束Ⅱ的FA值与MMSE(右侧r=0.672,P=0.033,左侧r=0.919,P<0.01)和MoCA(右侧r=0,747,P=0.013;左侧r=0.679,P=0.031)评分呈正相关。结论轻中度AD患者存在联络纤维损害且上纵束Ⅱ的损害程度与认知功能密切相关。     

SWI及DWI对高血压颅内微出血的检测价值

目的:评估SWI及DWI技术检测高血压患者脑微出血(cerebral microbleeds,CMBs)病变的临床价值。方法:收集40例原发性高血压患者,分为低-中危组及高-极高危组,同时收集同期40例健康成人作为对照组,共80例。2组均行MRI颅脑常规序列、DWI及SWI检查。对SWI及DWI显示CMBs的阳性率及CMBs数量进行统计学分析。结果:高血压组中26例发现CMBs病灶,对照组为6例;高血压组CMBs病灶轻、中、重度均可见,对照组阳性患者中仅见轻度CMBs病灶;CMBs主要位于双侧基底节区及皮质-皮质下区。无论是对照组、低-中危组还是高-极高危组,SWI与DWI显示CMBs阳性率及CMBs数目差异均有统计学意义(P0.05);对照组与高-极高危组、低-中危组与高-极高危组CMBs阳性率及CMBs数目差异均有统计学意义(P0.01)。结论:SWI显示高血压患者CMBs优于DWI,当高血压患者怀疑CMBs时,SWI应作为首选检查方法。     

DWI与SWI在急性期脑梗死合并脑微出血诊断中的应用

目的 :探讨DWI、SWI对急性期脑梗死合并脑微出血(CMBs)的应用价值。方法 :选取急性期脑梗死患者41例,采用GE 1.5 T超导型MRI仪,行常规MRI及DWI、SWI序列,比较DWI、SWI对急性期脑梗死及急性期脑梗死合并CMBs的检出率。结果:MRI各序列对急性期脑梗死检出阳性率分别为:常规MRI 75.61%,DWI 100.00%,SWI 68.29%,差异有统计学意义(P0.05),DWI序列急性脑梗死阳性检出率高于常规MRI检查和SWI序列;MRI各序列对急性期脑梗死合并CMBs检出阳性率分别为:常规MRI 0,DWI 9.76%,SWI(ESWAN)46.43%,差异有统计学意义(P0.05),SWI急性脑梗死CMBs灶阳性检出率高于常规MRI检查和DWI。DWI b值=0 s/mm2的图像能发现少许CMBs病灶。结论:DWI结合SWI的对急性期脑梗死合并CMBs的诊断具有重要价值。     

缺血性脑卒中患者急性期认知功能状况调查与分析

目的:调查了解缺血性脑卒中患者急性期认知功能状况。方法:采用简易精神状态检查量表(MMSE)及蒙特利尔认知评估量表(MoCA)对缺血性脑卒中48例发病7天内的认知功能状况进行测评。结果:58.3%的缺血性脑卒中患者存在认知功能障碍;视空间与执行功能、命名、语言重复及流畅得分与MoCA总分显著相关(P<0.05),其余各项得分与MoCA总分无显著相关性(P>0.05);视空间与执行功能、命名、计算力及抽象能力标准化回归系数与总分显著相关(P<0.05),按照标准化回归系数高低排序依次为视空间与执行功能、命名、计算力及抽象能力。结论:58.3%的缺血性脑卒中患者存在认知功能障碍,应进行有针对性的干预。     

Association Fibers Integrity in Alzheimer' s Disease

目的 采用磁共振扩散张量成像( diffusion tensor imaging,DTI)观察阿尔茨海默病(Alzheimer's disease,AD)患者联络纤维的改变情况.资料与方法 对10例轻中度AD患者和18名健康老年人(对照组)行常规MRI [(T1WI、T2WI、T2液体衰减反转恢复序列(FLAIR)]及DTI检查,DTI测量双侧扣带束、上纵束Ⅱ、钩束及额枕下束8个感兴趣区(ROI)的部分各向异性分数(FA)值.采用简易精神状态量表(MMSE)和蒙特利尔认知评估量表(MoCA)对AD患者的认知功能进行测定.结果 与对照组相比,AD组MMSE评分和MoCA评分较对照组明显下降(P＜0.05),AD组常规MRI上ROI白质信号无明显变化,ROI部位的FA值均显著下降(P＜0.05),且上纵束Ⅱ的FA值与MMSE(右侧r＝0.672,P＝0.033,左侧r＝0.919,P＜0.01)和MoCA(右侧r＝0,747,P＝0.013;左侧r＝0.679,P＝0.031)评分呈正相关.结论 轻中度AD患者存在联络纤维损害且上纵束Ⅱ的损害程度与认知功能密切相关.     

SWI在糖尿病患者伴发脑内微出血中的诊断应用

目的：通过磁敏感加权成像（SWI）检查,探讨糖尿病患者伴发脑内微出血（CMBs）的发生率,以及其与血糖水平、急性脑卒中、白质疏松程度等的相关性。方法：61例糖尿病患者中单纯糖尿病21例,糖尿病合并高血压40例。患者均行T2wI、T1wI、DwI及ESWAN序列SWI扫描,统计CMBs发生率、数目、分布。分析CMBs与其它,临床表现和影像学表现的相关性。结果：61例中有15例检出CMBs（发生率24．6％）,均发生在糖尿病合并高血压组,单纯糖尿病组未发现CMBs。糖尿病伴有急性脑卒中患者33例,其中13例发生CMBs（发生率为39．4％）。15例脑内有CMBs组与46例脑内无CMBs组的血糖水平（最高值、最低值、控制值）、年龄和病程采用t检验进行比较,发现有CMBs组平均空腹血糖最低值低于无cMBs组,且差异有统计学意义（t=0．046,P〈0．05）;61例患者按脑白质疏松程度分为4组,采用Fisher’s精确概率法检验,发现各组的CMBs发生率不N,且差异有高度统计学意义（P〈0．01）。结论：swI能清晰显示糖尿病患者CMBs;单纯糖尿病患者不易发生CMBs,糖尿病合并高血压CMBs发生率明显增加;糖尿病患者伴有急性脑卒中和脑白质疏松时易发生CMBs。     

SWI在脑微出血与急性期脑梗死后出血转化的相关性研究

目的探讨急性脑梗死脑出血转化(HT)与微出血(CMBs)的相关性。方法回顾性分析发病在24 h内经临床及扩散加权成像(DWI)确诊的急性期脑梗死患者资料72例,根据磁敏感加权成像(SWI)图像梗死灶内是否出现极低信号分为梗死后出血转化组(HT组)和单纯脑梗死组(对照组)。同时对病灶以外CMBs经两名影像学医师诊断记为CMBs阳性共32例,其中对照组24例(24/62,38.7%),HT组8例(8/10,80%)。根据CMBs分布分为脑叶组和脑深部组,对照组脑叶8例(8/24,33.33%),脑深部16例(16/24,66.67%)。HT组脑叶7例(7/8,87.5%),脑深部1例(1/8,12.5%)。结果两组CMBs检出率及发生部位差异均有统计学意义(P值<0.05)。结论梗死后HT与CMBs的发生率和发生部位相关,SWI可检出CMBs,预示微血管的出血倾向,预测急性期脑梗死HT的危险性,进而为溶栓治疗提供可能的依据。     

卒中患者脑微出血的MRI特点及其临床意义

目的 探讨卒中患者脑微出血（CMBs）的MRI特点及其临床意义，并比较MRI不同扫描序列检出CMBs的能力。方法 卒中患者60例，分为脑缺血组（34例）和脑出血组（26例），以同期查体的60岁以上健康老年人为对照组（30例）。采用常规MRI（包括SE T1WI和FSE T2WI）、扩散加权成像（DWI）、梯度回波T2加权成像（GRE-T2WI）和平面回波成像（EPI）检查，分别统计各组CMBs、腔隙性梗死、脑白质稀疏情况，同时记录卒中患者的高血压、糖尿病、卒中病史，比较不同扫描序列检出CMBs的差异。结果 CMBs在缺血组、出血组和对照组的发生率分别为29．4％，61．5％和6．7％。CMBs最常见于基底节／丘脑区。CMBs与高血压、卒中病史相关（P〈0．01），而与糖尿病无关（P〉0．05）。CMBs的数目与腔隙性脑梗死的数目和脑白质的改变程度成正相关（P〈0．01）。常规MRI和DWI均不能显示CMBs，EPI与GRE-T2WI检出CMBs的差异无统计学意义（P〉0．05）。结论 脑卒中患者多发性CMBs的存在提示微血管病变的严重程度和出血倾向，对于临床治疗决策具有重要的指导意义。GRE-T2WI是检测CMBs的首选方法，EPI可作为GRE-T2WI的补充手段。     

SWI对急性脑梗死静脉溶栓治疗决策的价值

目的 探讨磁共振磁敏感加权成像(SWI)序列在急性脑梗死静脉溶栓治疗决策中的价值.方法 依据SWI扫描是否存在脑组织微量出血(CMBs),将35例急性脑梗死患者分为实验组(存在CMBs)14例和对照组(无CMBs)21例.静脉溶栓后,通过SWI检测计数发生出血性转化(HT)的例数,比较实验组和对照组之间发生HT是否存在统计学差异(P<0.05).结果 静脉溶栓治疗后,实验组14例梗死灶中12例发生HT,对照组21例仅2例发生HT,2组间HT发生存在统计学差异(P<0.05).结论 磁共振SWI能敏感检测CMBs的存在,间接评估血脑屏障(BBB)及血管壁状态,和时间窗一起作为静脉溶栓治疗方案的决策依据.     

Cerebral Microbleeds: Different Prevalence,Topography, and Risk Factors Depending on Dementia Diagnosis—The Karolinska Imaging Dementia Study

BACKGROUND AND PURPOSE:Cerebral microbleeds are thought to represent cerebral amyloid angiopathy when in lobar regions of the brain and hypertensive arteriopathy when in deep and infratentorial locations. By studying cerebral microbleeds, their topography, and risk factors, we aimed to gain an insight into the vascular and amyloid pathology of dementia diagnoses and increase the understanding of cerebral microbleeds in dementia.MATERIALS AND METHODS:We analyzed 1504 patients (53% women; mean age, 63 ± 10 years; 10 different dementia diagnoses) in this study. All patients underwent MR imaging as part of the dementia investigation, and all their clinical parameters were recorded.RESULTS:Among the 1504 patients with dementia, 22% had cerebral microbleeds. Cerebral microbleed topography was predominantly lobar (P = .01) and occipital (P = .007) in Alzheimer disease. Patients with cerebral microbleeds were significantly older (P < .001), were more frequently male (P < .001), had lower cognitive scores (P = .006), and more often had hypertension (P < .001). Risk factors for cerebral microbleeds varied depending on the dementia diagnosis. Odds ratios for having cerebral microbleeds increased with the number of risk factors (hypertension, hyperlipidemia, diabetes, male sex, and age 65 and older) in the whole patient group and increased differently in the separate dementia diagnoses.CONCLUSIONS:Prevalence, topography, and risk factors of cerebral microbleeds vary depending on the dementia diagnosis and reflect the inherent pathology of different dementia diagnoses. Because cerebral microbleeds are seen as possible predictors of intracerebral hemorrhage, their increasing prevalence with an increasing number of risk factors, as shown in our study, may require taking the number of risk factors into account when deciding on anticoagulant therapy in dementia.

Cerebral microbleeds (CMBs) are not usually seen on conventional MR imaging and CT but have been increasingly detected due to the more frequent use of the T2* and SWI MR imaging sequences, sensitive to minute amounts of blood. On MR imaging, CMBs are seen as round hypointense foci, and histologically they are represented by hemosiderin deposits in macrophages, mainly located around small vessels.^1,2 The pathology of CMBs is thought to vary depending on the location: Deep and infratentorial CMBs represent underlying hypertensive arteriopathy, whereas lobar CMBs mainly represent vascular amyloid deposition, so-called cerebral amyloid angiopathy (CAA).³CAA and hypertension are common in patients with dementia. CAA is reported to be present in up to 98% of patients with Alzheimer disease in postmortem studies, and hypertension in middle-aged and elderly populations has been related to the development of dementia.^4,5 Studies have shown a higher prevalence of CMBs in patients with dementia compared with healthy populations. Alzheimer disease, for instance, is reported to have a CMB prevalence of 18%–32% versus 3%–11% in healthy populations imaged with MR field strengths of 1T–1.5T.^6–15 Consequently, CMBs are hypothesized to play an important role in the disease mechanisms of dementia as well as being a marker of the synergistic effects between vascular and amyloid pathology.¹⁶ Of further interest, CAA and hypertension are the most common causes of intracerebral hemorrhage, with CMBs being proposed as a possible predictor of intracerebral hemorrhage.¹⁷Investigating CMBs in dementia is of importance for further understanding the disease mechanisms of different dementia diagnoses and improved clinical and therapeutic treatment. CMBs and their location may give an insight into the vascular and amyloid pathology of dementia diagnoses and thus expose different dementia characteristics. Up-to-date studies on CMBs and dementia have been conducted mainly on small cohorts, without a standardized scale for CMB rating and with a scarcity of included dementia diagnoses. Furthermore, analyses have been made on a whole-cohort basis, rather than separating different dementia diagnoses and their respective CMB characteristics. In this study, we aimed to examine the prevalence, topography, and risk factors associated with CMBs in a large and diverse dementia population with subgroup analysis. By doing so, we hoped to gain insight in the pathophysiologic mechanisms in different dementia diagnoses. We hypothesized that CMB prevalence would be dependent on risk factors, depending on the dementia diagnosis, and that vascular risk factors would be important in the development of CMBs in dementia.     

Assessment of cerebral microbleeds by susceptibility-weighted imaging at 3T in patients with end-stage organ failure

Purpose

Cerebral microbleeds (CMBs) are small rounded lesions representing cerebral hemosiderin deposits surrounded by macrophages that results from previous microhemorrhages. The aim of this study was to review the distribution of cerebral microbleeds in patients with end-stage organ failure and their association with specific end-stage organ failure risk factors.

Materials and methods

Between August 2015 and June 2017, we evaluated 15 patients, 9 males, and 6 females, (mean age 65.5 years). Patients population was subdivided into three groups according to the organ failure: (a) chronic kidney failure (n = 8), (b) restrictive cardiomyopathy undergoing heart transplantation (n = 1), and (c) end-stage liver failure undergoing liver transplantation (n = 6). The MR exams were performed on a 3T MR unit and the SWI sequence was used for the detection of CMBs. CMBs were subdivided in supratentorial lobar distributed, supratentorial non-lobar distributed, and infratentorial distributed.

Results

A total of 91 microbleeds were observed in 15 patients. Fifty-nine CMBs lesions (64.8%) had supratentorial lobar distribution, 17 CMBs lesions (18.8%) had supratentorial non-lobar distribution and the remaining 15 CMBs lesions (16.4%) were infratentorial distributed. An overall predominance of supratentorial multiple lobar localizations was found in all types of end-stage organ failure. The presence of CMBs was significantly correlated with age, hypertension, and specific end-stage organ failure risk factors (p < 0.001).

Conclusions

CMBs are mostly founded in supratentorial lobar localization in end-stage organ failure. The improved detection of CMBs with SWI sequences may contribute to a more accurate identification of patients with cerebral risk factors to prevent complications during or after the organ transplantation.